:root {
  --bg: #f8fafc;
  --surface: #ffffff;
  --ink: #172033;
  --muted: #64748b;
  --line: #e2e8f0;
  --brand: #111827;
  --accent: #ff6b6b;
  --accent-soft: #fff1f2;
  --green: #14b8a6;
  --shadow: 0 18px 45px rgba(15, 23, 42, .08);
  color-scheme: light;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  color: var(--ink);
  background: linear-gradient(180deg, #fff 0%, var(--bg) 42%, #fff 100%);
  line-height: 1.7;
}
a { color: inherit; text-decoration: none; }
img, video { max-width: 100%; display: block; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(18px);
  background: rgba(255, 255, 255, .88);
  border-bottom: 1px solid var(--line);
}
.topbar {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand-lockup img { height: 44px; width: auto; }
.main-nav { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; justify-content: flex-end; }
.main-nav a {
  padding: 8px 12px;
  border-radius: 999px;
  color: var(--muted);
  font-size: 14px;
}
.main-nav a:hover, .main-nav a.active { background: var(--accent-soft); color: var(--brand); }
.brand-search {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto 14px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 10px;
  align-items: center;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 10px;
  box-shadow: 0 10px 22px rgba(15, 23, 42, .04);
}
.brand-search label { font-weight: 700; padding: 0 8px; }
.brand-search input {
  border: 0;
  outline: 0;
  background: #f1f5f9;
  min-height: 42px;
  border-radius: 14px;
  padding: 0 14px;
  font-size: 15px;
}
.brand-search button, .button {
  border: 0;
  border-radius: 999px;
  padding: 12px 18px;
  font-weight: 800;
  cursor: pointer;
  display: inline-flex;
  justify-content: center;
  align-items: center;
  min-height: 44px;
}
.search-hint { grid-column: 1 / -1; margin: 0; color: var(--muted); font-size: 13px; }
.section-shell { width: min(1180px, calc(100% - 32px)); margin: 0 auto; padding: 72px 0; }
.hero { display: grid; grid-template-columns: 1.02fr .98fr; gap: 42px; align-items: center; }
.eyebrow { color: var(--accent); font-weight: 900; letter-spacing: .08em; text-transform: uppercase; margin: 0 0 12px; }
h1, h2, h3 { line-height: 1.18; margin: 0 0 16px; }
h1 { font-size: clamp(40px, 7vw, 78px); letter-spacing: -0.06em; }
h2 { font-size: clamp(28px, 4vw, 44px); letter-spacing: -0.04em; }
h3 { font-size: 21px; }
.lead, .section-intro { font-size: 18px; color: var(--muted); max-width: 760px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; margin: 28px 0; }
.button.primary { background: var(--brand); color: #fff; box-shadow: var(--shadow); }
.button.secondary { background: var(--accent-soft); color: var(--brand); }
.trust-metrics { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin: 28px 0 0; }
.trust-metrics div { background: var(--surface); border: 1px solid var(--line); border-radius: 20px; padding: 18px; box-shadow: var(--shadow); }
.trust-metrics dt { color: var(--muted); font-size: 13px; }
.trust-metrics dd { margin: 4px 0 0; font-size: 24px; font-weight: 900; }
.hero-visual { margin: 0; position: relative; }
.hero-visual img { border-radius: 32px; box-shadow: var(--shadow); aspect-ratio: 1.16; object-fit: cover; }
figcaption, .image-description { color: var(--muted); font-size: 13px; margin-top: 10px; }
.two-column { display: grid; grid-template-columns: 1fr .72fr; gap: 28px; }
.principles, .guide-card, .content-card, .review-card, blockquote, .scene-grid article, .title-list article {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 28px;
  padding: 26px;
  box-shadow: var(--shadow);
}
.principles ul, .steps, .product-card ul { padding-left: 18px; margin: 10px 0 0; }
.product-grid, .review-grid, .quote-grid, .scene-grid, .title-list, .contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 28px;
}
.product-grid { grid-template-columns: repeat(4, 1fr); }
.product-card {
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 28px;
  box-shadow: var(--shadow);
}
.product-card.large { display: grid; grid-template-columns: .8fr 1fr; grid-column: span 2; }
.product-card img { width: 100%; height: 210px; object-fit: cover; }
.product-card.large img { height: 100%; min-height: 300px; }
.product-body { padding: 22px; }
.tag, .video-badge, .tags span {
  display: inline-flex;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  padding: 5px 10px;
  font-size: 12px;
  font-weight: 900;
}
.video-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 28px; }
.video-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 30px;
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform .25s ease, box-shadow .25s ease;
}
.video-card:hover, .video-card:focus { transform: translateY(-5px); box-shadow: 0 24px 60px rgba(15,23,42,.14); outline: none; }
.poster-wrap { position: relative; background: #0f172a; aspect-ratio: 16 / 10; overflow: hidden; }
.demo-video { width: 100%; height: 100%; object-fit: cover; opacity: .94; }
.play-indicator {
  position: absolute;
  inset: 50% auto auto 50%;
  transform: translate(-50%, -50%) scale(.8);
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: rgba(255,255,255,.92);
  color: var(--brand);
  display: grid;
  place-items: center;
  font-size: 28px;
  opacity: 0;
  transition: .25s ease;
  box-shadow: var(--shadow);
}
.video-card:hover .play-indicator, .video-card:focus .play-indicator { opacity: 1; transform: translate(-50%, -50%) scale(1); }
.video-badge { position: absolute; left: 14px; top: 14px; background: rgba(255,255,255,.92); }
.video-info { padding: 22px; }
.stats { display: flex; gap: 8px; flex-wrap: wrap; color: var(--muted); font-size: 13px; margin: 14px 0; }
.stats span { background: #f8fafc; border: 1px solid var(--line); padding: 5px 8px; border-radius: 999px; }
.tags { display: flex; gap: 8px; flex-wrap: wrap; }
.review-grid { grid-template-columns: repeat(5, 1fr); }
.review-card small { color: var(--muted); }
blockquote { margin: 0; }
blockquote p { font-size: 20px; margin-top: 0; }
.faq-list { display: grid; gap: 12px; margin-top: 24px; }
details {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 18px 20px;
  box-shadow: 0 8px 18px rgba(15,23,42,.04);
}
summary { cursor: pointer; font-weight: 900; }
.contact-strip { display: flex; align-items: center; justify-content: space-between; gap: 24px; background: var(--brand); color: #fff; border-radius: 36px; padding: 42px; }
.contact-strip .eyebrow, .contact-strip p { color: #fff; opacity: .9; }
.inner-main .breadcrumb { width: min(1180px, calc(100% - 32px)); margin: 28px auto 0; }
.breadcrumb { color: var(--muted); display: flex; flex-wrap: wrap; gap: 8px; font-size: 14px; }
.inner-hero { padding-top: 46px; padding-bottom: 32px; }
.content-stack { display: grid; gap: 18px; padding-top: 24px; }
.site-footer { margin-top: 70px; background: #0f172a; color: #e2e8f0; padding: 54px 0 24px; }
.footer-grid { width: min(1180px, calc(100% - 32px)); margin: 0 auto; display: grid; grid-template-columns: 1.2fr .8fr .8fr; gap: 28px; }
.footer-grid a { display: block; color: #cbd5e1; margin: 7px 0; }
.footer-grid h2 { font-size: 18px; }
.copyright { width: min(1180px, calc(100% - 32px)); margin: 34px auto 0; padding-top: 20px; border-top: 1px solid rgba(255,255,255,.12); color: #94a3b8; }
@media (max-width: 980px) {
  .hero, .two-column, .footer-grid { grid-template-columns: 1fr; }
  .product-grid, .video-grid, .review-grid, .quote-grid, .scene-grid, .title-list, .contact-grid { grid-template-columns: repeat(2, 1fr); }
  .product-card.large { grid-column: span 1; grid-template-columns: 1fr; }
  .topbar { align-items: flex-start; flex-direction: column; padding: 16px 0; }
  .main-nav { justify-content: flex-start; }
}
@media (max-width: 640px) {
  .section-shell { padding: 46px 0; }
  .brand-search { grid-template-columns: 1fr; }
  .product-grid, .video-grid, .review-grid, .quote-grid, .scene-grid, .title-list, .contact-grid, .trust-metrics { grid-template-columns: 1fr; }
  h1 { font-size: 38px; }
  .contact-strip { align-items: flex-start; flex-direction: column; border-radius: 26px; padding: 28px; }
}